In wireless networks in which wireless devices are included in or used in vehicles, there may be highly varying topologies and/or conditions experienced over time. For many applications, it may be desirable to wirelessly communicate a relatively large file to a wireless device in a vehicle where the air link resources are limited. During some times, a vehicle may be static for an extended period of time, while during other times a vehicle may be in motion. In addition, some geographic locations may be more favorable than others for communicating the file, e.g., due to proximity to a base station or other device which is broadcasting the file on a recurring basis. A vehicle may not be able to remain in the vicinity of a base station long enough to recover an entire file.
A simple approach is for a wireless device, which has received some portions of a file to rebroadcast the file portions that it has received, regardless of the conditions or environment. Thus over time, wireless devices may acquire complete files by piecing together received file portions transmitted from base stations and re-transmitted from other wireless devices. However, simple rebroadcast of received file portions may tend to result in redundant file portion transmissions, and may prolong the time until a wireless device acquires a complete file, particularly in a highly dynamic environment.
Based on the above discussion, there is a need for new methods and apparatus to efficiently communicate a file in a varying environment including mobility.